text: In this case, an extra freedom degree is added via a relatively small work input W (maximum work consumption, Eq.(9) with ΔG ≤ W), and Eq.(10) becomes,
  If W is expressed as a fraction f of the process heat Q (Eq.(14)), Eq.(15) becomes after reorganization,
   Using a work input equals to a fraction f of the heat input is equivalent relative to the choice of the reactions to operate a pure similar thermochemical cycle but with a hot source with a temperature increased by the same proportion f.
  Naturally, this decreases the heat-to-work efficiency in the same proportion f. Consequently, if one want a process similar to a thermochemical cycle operating with a 2000K heat source (instead of 1000K), the maximum heat-to-work efficiency is twice lower. As real efficiencies are often significantly lower than ideal one, such a process is thus strongly limited.
  Practically, use of work is restricted to key steps such as product separations, where techniques relying on work (e.g. electrolysis) might sometimes have fewer issues than those using only heat (e.g. distillations)